Pomegranate (Punica granatum L.) is extensively cultivated in Middle East especially in Iran. For centuries, this fruit has been used in Iranian herbal medicine. Pomegranate peel, seed and juice ...contain considerable amounts of phenolic compounds and have antioxidant activity. Pomegranate peels, juice and seeds from three regions of Natanz, Shahreza, and Doorak were obtained. Antioxidant activity, total phenolic, flavonoids, and flavonols contents of pomegranate peels, seeds and juices extracts were analyzed. The β-carotene bleaching test and Folin–Ciocalteu method were applied in this study. The pomegranate peel extract showed high levels of antioxidant activity in comparison to seeds and juices. Doorak peel by 58% had the highest antioxidant activity among two other peels. Total phenolics, flavonoids, and flavonols contents of pomegranate peel were evaluated much more higher than seeds and juices. The significant positive correlation between antioxidant activity and total phenolics was reported. According to achieved results, high antioxidant capacity of pomegranate especially peel, had shed light to use them as natural food preservatives.
•All parts of pomegranate had antioxidant activity with high total phenolic, flavonoid and flavonol contents.•The Highest antioxidant activity of pomegranate was measured in peel extract.•A positive correlation between antioxidant activity and total phenolic content were reported.
Common bean is a legume important in Mediterranean diet with interesting nutritional food characteristics due to its proteins, fibers and antioxidant activity. There is an increased interest among ...consumers in foods rich in natural antioxidants for maintaining and improving health. Beyond this, beans are a low-price food and an excellent complement for the population with low income. There are some differences in the phenolic and flavonoid compounds content and antioxidant capacity between accessions of common bean. In this study, 15 traditional Portuguese and 1 Greek accessions of Phaseolus vulgaris L. were analyzed. Total phenols, ortho-diphenols and flavonoid contents were investigated and antioxidant activity were measured by different assays (DPPH, ABTS) which may give a better characterization of this activity.
•The Schiff bases 1–3 from 2-amino-4‑tert-butylphenol were synthesized and characterized by NMR,IR,HRMS and UV–vis.•The crystal structures of 1 and 3 were established by single crystal X-ray ...diffraction.•The DPPH radical scavenging rates of compounds 1 (92.62%) and 2 (91.05%) are comparable to that of Vitamin C (98.31%) at the concentration of 1.0 mg/mL.•The DFT theoretical results show that the ET-PT mechanism is reasonable and in line with the experimental well.
Schiff bases are chemical compounds formed from the condensation reaction of aldehydes or ketones with amines. In medicinal chemistry, these compounds have received widespread attention due to significant biological activities, including antioxidant, antibacterial, antifungal, antiviral, antitumor, and anti-inflammatory. Herein, three Schiff base compounds, namely 2-(3, 5-di‑tert‑butyl‑2-hydroxybenzylideneamino)-4‑tert-butylphenol (1), 2-(4-(diethylamino)-2-hydroxybenzylideneamino)-4‑tert-butylphenol (2) and (1E)-1-((5‑tert‑butyl‑2-hydroxyphenylamino)methylene)naphthalen-2(1H)-one (3) were synthesized and characterized by NMR,IR,HRMS and UV–vis. Moreover, the structures of compounds 1 and 3 were determined by single crystal X-ray diffraction techniques. The theoretically simulated NMR, IR and the UV-visible absorption spectra have been compared with the experimental datas. Based on the absorbed UV spectra and TD-DFT calculations, assignment of the absorption bands are carried out. The antioxidant capacity of three butylphenol derivatives was evaluated by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging experiments using Vitamin C as a standard drug. The scavenging rates of compounds 1 (92.62%) and 2 (91.05%) were comparable to that of Vitamin C (98.31%) at the concentration of 1.0 mg/mL. In order to investigate the DPPH free radical scavenging mechanism, a theoretical study based on density functional theory (DFT) was performed. The results show that ET-PT mechanism is favored which is in agreement with the experimental results.
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Functional films were made by solution casting using three different types of carbohydrates (agar, chitosan, and carrageenan) and curcumin. Field emission scanning electron microscopy (FE-SEM) and ...Fourier transform infrared spectroscopy (FTIR) test results showed that curcumin is homogeneously dispersed within the polymer matrix. Addition of a small amount of curcumin (1 wt%) increased the UV-blocking, swelling ratio, surface hydrophobicity, and water vapor barrier property of the carbohydrate-based films. The release rate of curcumin was influenced by the type of polymer matrix, i.e. the carrageenan-based film exhibited the fastest release of curcumin following agar and chitosan-based films. Also, the composite films exhibited high antioxidant activity and some antibacterial property depending on the type of carbohydrate, which was consistent with the release rate of curcumin, water solubility and swelling ratio of the composite films. The curcumin-incorporated carbohydrate films with increased physical and functional properties can be used for active food packaging films.
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•Curcumin-incorporated various carbohydrate-based composite films were prepared.•UV-blocking, swelling, surface hydrophobicity and WVP properties were enhanced.•Curcumin-incorporated film exhibited strong antioxidant and some antimicrobial activity.•Properties of the composite films depended on the type of carbohydrate polymer matrix.
Ferulic acid (FA) is a natural antioxidant with antimicrobial activity and its application is restricted due to poor water solubility. To overcome this limitation, FA was entrapped into cyclodextrin ...nanosponges (CD-NSs). The antibacterial activity of FA was assessed using the microdilution method which showed a higher antibacterial activity after encapsulation. A controlled release of FA was observed in simulated gastrointestinal environment and food simulants. Furthermore, the application of FA-loaded nanosponges (FA-NS) was investigated in pomegranate juice (PJ). Anthocyanins are the main phenolic compounds of PJ that are sensitive to different environmental conditions. Copigmentation of anthocyanins with other phenolic acids can help to improve their stabilization. The antioxidant activity and phenolic content of all PJ samples (free PJ and PJ containing pure FA and FA-NS) were enhanced during storage while the anthocyanin content of all PJ samples was lessened during the storage. However, the samples containing FA-NS compared to the other samples could better preserve the anthocyanin content. Enhanced solubility of FA after incorporation into CD-NSs can induce higher interaction of FA with other components in PJ and improve their stability to preserve during the storage. These results may pave the way for the application of FA-NS as a copigment agent in juices containing anthocyanins to improve their stability during storage.
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An investigation was carried out to elucidate growth, anatomical, physiological, and major ROS detoxification pathways involved in the tolerance of A. tricolor under salinity stress. Both VA14 and ...VA3 varieties exhibited the reduction in relative water content (RWC), photosynthetic pigments, growth, increased electrolyte leakage (EL), and leaf anatomy adaptation under salinity stress, whereas VA14 was well adapted and performed better compared to VA3. Higher ROS accumulation was demonstrated in the sensitive variety (VA3) in comparison to the tolerant variety (VA14). Salinity stress changed the cellular antioxidant pool by increasing total carotenoids, ascorbate, proline, total polyphenol content (TPC), total flavonoid content (TFC), and total antioxidant capacity (TAC) in both varieties. Although a higher increment was demonstrated in the tolerant variety, the proline increment was much more pronounced in the sensitive variety. Non-enzymatic antioxidant, ascorbate, carotenoids, TPC, TFC, TAC, and antioxidant enzymes SOD and APX were noted to be a major H2O2 detoxifier in the tolerant A. tricolor variety, where there is a comparatively lower H2O2 load. It was complemented by GPOX and CAT activity at a comparatively higher H2O2 load (in the sensitive variety). SOD contributed to the dismutation of superoxide radical (SOR) both in the tolerant and sensitive varieties; however, it greatly contributed to the dismutation of SOR in the tolerant variety. The increase in SOD, ascorbate, and APX makes it predominantly evident that SOD and the AsA-GSH cycle had greatly contributed to quench reactive oxygen species (ROS) of the tolerant variety of A. tricolor.
•Ten phenolic compounds have been identified for the first time in finger millet.•Catechin and epicatechin are the major extractable flavonoids in finger millet.•Ferulic acid is the major bound ...phenolic compound in finger millet.•Colored finger millets have higher phenolic compounds than non-colored ones.
The profiles of phenolic compounds and antioxidant capacities of four finger millet varieties harvested in northern Malawi were investigated. The total phenolics, flavonoids and condensed tannins in the free fractions ranged from 114.43 to 179.19 mg ferulic acid equivalent (FAE)/100 g, 90.24 to 202.94 mg catechin equivalent (CE)/100 g and 31.76 to 83.59 mg CE/100 g, respectively. Total phenolic contents of the bound fractions ranged from 58.27 to 123.23 mg FAE/100 g. Twenty phenolic compounds were identified in the free fractions including eighteen flavonoids, with catechin and epicatechin being the predominant flavonoids. Seventeen phenolic compounds were identified in the bound fractions, with ferulic acid being the predominant one. Ten of the identified polyphenols were firstly reported in finger millet. Darker colored finger millet varieties had higher phenolic contents and antioxidant properties than the lighter colored ones. Finger millet can be used as healthy food material and natural antioxidant resource.
Polygonatum kingianum is usually used as a Chinese traditional homology of medicine and foods. P. kingianum polysaccharides exhibit various biological activities. To date, the processing of P. ...kingianum with Lactobacillus fermentation has been rarely explored. This study investigated the optimum fermentation conditions of P. kingianum using Lactobacillus plantarum and Lactobacillus rhamnosus by response surface methodology (RSM), followed by the extraction and characterization of fermented polysaccharides (namely MFP and SFP respectively), in contrast to non-fermented polysaccharide (NFP). Their changes in physicochemical properties, antioxidant, and cardioprotective activities were studied. High-performance size-exclusion chromatography analysis results demonstrated that a reduction in the proportion of the lower molecular weight fraction II (2.9 kD) of MFP and SFP. Compared to NFP, both MFP and SFP showed increased levels of galactose, galacturonic acid, and rhamnose, but decreased mannose, galactosamine, glucuronic acid, glucose, fucose, and fructose. Furthermore, the 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assays revealed the higher antioxidant activities of MFP and SFP. Bioassay results showed that MFP and SFP possessed cardioprotective activities against hypoxia/reoxygenation injury in cardiomyocytes through the alleviation of oxidative stress and the inhibition of cell apoptosis. Collectively, these results could provide a reference for largescale production of polysaccharides form P. kingianum using Lactobacillus in medical and food industries.
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•Process for the fermentation of Polygonatum kingianum was optimized.•Lactobacillus fermentation improved antioxidant activity of Polygonatum kingianum.•Fermentation altered the physicochemical properties of polysaccharides.•Fermented-polysaccharides exhibited superior cardioprotective potential.
There is a growing interest for healthy non-bovine functional dairy products. Therefore, in the present study, an aqueous polyphenol-rich artichoke extract (AE) and two Bifidobacterium strains of ...human origin (B. pseudolongum INIA P2 and B. longum INIA P132) were added, alone or in combination with AE, for the manufacture of six sheep milk cheeses. In general, addition of 1.25 g of lyophilized AE per 100 g of curd did not affect cheese pH, dry matter, lactoccci starter counts or organic acid levels during ripening. Bifidobacterial strains showed good viability in cheeses with AE during ripening and after simulated major gastrointestinal conditions. Cheeses with AE showed improved functional properties, with significantly (P < 0.01) higher total polyphenol content and, especially, antioxidant activity The cheese with AE and strain INIA P2 fulfil the definition of a symbiotic cheese. It contains prebiotic compounds and Bifidobacterium at adequate levels to sustain a therapeutic effect, which are able to survive major gastrointestinal conditions. This cheese could confer beneficial effects on consumers’ health by contributing to the host antioxidant capacity and increasing polyphenol bioavailability.
•Artichoke extract (AE) did not affect cheese pH, dry matter, colour or microbiota.•AE increased cheese proteolysis, polyphenol content and antioxidant activity.•INIA P2 increased AE polyphenol bioavailability and showed good viability in cheese.•AE and bifidobacteria affected cheese volatile profile.•Symbiotic cheese with AE and INIA P2 may provide polyphenol health benefits.
The Special Issue “Extractable and Non-Extractable Antioxidants” gives an updated view on antioxidants—both in their extractable and non-extractable form—in the different food groups, their products ...thereof, and food preparations as well as byproducts and biomass waste. The potential beneficial properties of these compounds and nutraceutical formulations are described in the various studies covered in this Special Issue.
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